Fabrication of FGF-2 immobilized electrospun gelatin nanofibers for tissue engineering

Conjugated gelatin nanofibers were fabricated by electrospinning, followed by a simple glutaraldehyde cross-linking procedure and avidin conjugation. Then, biotinylated growth factors were immobilized onto the surface of the fibers through avidin-biotin covalent binding. The immobilization of growth factors was confirmed through immunostaining using fluorescence microscopy and microplate spectrophotometry. Adipose derived stem cells (ASCs) were cultured to examine the effect of immobilized growth factors on cell proliferation using the cell counting Kit-8 (CCK-8) assay. Gelatin nanofibers with no growth factors attached and growth factors in suspension within media were used as controls. Growth factors were successfully immobilized onto the surface, in amounts corresponding to the concentrations applied, and increased cell proliferation to a higher extend than growth factors in suspension. Our results suggest that this controllable scaffolding strategy provides an effective system for growth factors delivery in tissues, suitable for engineering applications.